Wheeled crane



March 1952 R. 6. LE TOURNEAU WHEELED CRANE Filed Aug. 23, 1948 INVENTOR Rabi. GZe'Zburneau ATTORNEYS Patented Mar. 11, 1952 WHEELED CRANE Robert G. Le Tourneau, Longview, Tex., assignor to R. G. Le Tourneau, Inc., Stockton, Califi, a corporation of California Application August 23, 1948, Serial No. 45,726

Claims.

the lift fork assembly on the elevator carriage for folding from a rearwardly projecting working position, to an upwardly projecting nonworking or out-of-the-way position so as to then permit of use of the crane without said lift fork assembly.

An additional object of the invention is to provide novel, releasable latch means, for the lift fork assembly, adapted to hold the latter in folded or non-working position.

It is also an object of the invention to provide the crane with a novel bumper in position for engagement by the elevator frame upon forward tilting thereof; such bumper also serving to limit the maximum forward tilt of said elevator frame.

A further object of the invention is to provide practical and reliable improvements in wheeled cranes, which will be exceedingly effective for the purpose for which they are designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the followin specification and claims.

In the drawings:

Fig. 1 is a side elevation of a wheeled crane embodying the present invention.

Fig. 2 is an enlarged fragmentary elevation of the latch unit corresponding to one of the fork legs.

Fig. 3 is an enlarged fragmentary elevation, mainly in section, of the bumper unit.

Referring now more particularly to the characters of reference on the drawings, the invention is embodied in a crane which includes a rigid longitudinally extending body I connected, at its forward end, to a tractor 2 by means of a power steering and coupling unit, indicated generally at 3.

The body I is supported, at its rear end, by means of rear wheels 4.

An elevator frame 5 upstands from the rear end of the crane and is pivotally mounted for tilting movement in a longitudinal vertical plane;

the forward limit of such tilting movement of the elevator frame 5 being indicated in dotted lines in Fig. 1.

Tilting of the elevator frame 5, i. e. its swinging adjustment in a longitudinal vertical plane, is accomplished by means of a cable operated, tilt control assembly 6 connected between said frame 5 and an upstanding A-frame 1 on the body I. The tilt control assembly 6 is actuated by a Winch 8.

The elevator frame 5 is fitted therein with a roller mounted elevator carriage 9, and a boom I0 is fixed in connection with and projects rearwardly from, said elevator carriage. The boom I0 supports a hoist cable ll operated by a winch I2.

The elevator carriage 9 is vertically adjusted by a control cable system [3 which includes a winch l4.

Under many working conditions it is desirable that the crane be provided with a-lift fork assembly, and the present invention contemplates the embodiment of such an assembly, as follows:

The fork unit, which is provided for the crane, comprises a pair of transversely spaced fork legs l5, and as the mounting and operation of each is identical a description of one will sufiice for both.

Each fork leg I 5 is normaly disposed in an upstanding position to the rear of the elevator carriage 9 and to one side of the inner end portion Illa of the lbOOm Ill, and which portion is practically a part of the carriage 9, as will be evident.

Adjacent, but short of, the inner end of the fork leg I5 the latter is pivotally connected by cooperating ears and lugs I6 and I! on the fork leg l5 and the lower end of the elevator carriage 9, respectively; said ears and lugs I B and I! being secured together by a pivot pin I8.

Each fork leg I5, when in its upwardly folded position, as in full lines in Fig. 1, abuts a stop I9 aliixed to the adjacent side of the inner end portion Illa of the boom l9. At the same time such fork leg I5 is engaged, from the rear and at its upper end, by a releasable latch unit 20, like- Wise aflixed to the boom portion I (la, but at a point somewhat above and to the rear of the stop I9. 7

Thelatch unit 20, which cooperates with each fork leg I5, is shown in detail in Fig. 2, and comprises:

A vertically movable, spring-pressed latch pin 2| extends in guided relation through a yoke 22, which yoke is secured to the boom Ill. A stop collar 23 on the latch pin 2| limits the downward motion of the latter; said pin being springurged downwardly by a compression spring 24 surrounding the pin between the stop collar 23 and the upper portion of the yoke 22.

An eccentric cam 25 is pivoted, as at 26, to the latch pin 2| above, and cooperating with, the top of the yoke 22. A hand lever 21 is fixed to and extends from the cam 25 in actuating relation to the latter. By swinging the hand lever 21 in one direction, the eccentric cam 25 pulls upwardly on the latch pin 2|, against the spring 24, to release such pin from the upper end of-the corresponding fork leg [5.

In this manner each fork leg l5 can be released for downward swinging motion from its normally upstanding, out-of-the-way position, as in full lines in Fig. l, to a rearwardly projecting working position, as in dotted lines in said figure. In working position each fork leg l5 abuts, .at'its inner end, upwardly against a corresponding stop 28 on the bottom of the elevator carriage 9. It is thus a very simple manual operation to change the position of each fork leg l5. When the lift fork assembly is in its rearwardly projecting working position, the crane is used-in thesame manner as a k lift truck; the'wo k ns e vation of the legs l5 being adjustable by up and down travel of the elevator carriage 9. Additiona y. t e=.e1eva ma be ti t d f :warolly to cause raising of :the lift fork assembly at its rear or outer end.

When the elevator frame .5 is tilted forwardly by the tilt control assembly 6, such motion is limited to a maximum extent predetermined by a bumper unit 29. A cross bar 30 is mounted on the A-frame 1, and is fitted with one or more of the bumper units 29 positioned for engagement with parts of the elevator frame 5 as the latter tilts forwardly. Each such bumper unit 29 is constructed as follows:

A fixed sleeve 3| is rigidly mounted on the cross bar 30 and extends at arearward and upward incline, and a movable sleeve 32 partially telescopes the fixed sleeve 3| from the free end of the latter. A heavy-duty compression spring 33 is disposed ,in the sleeve assemblyand bears, at the inner end, against a base plate 34 mounted in the fixed sleeve 3| by means includin an internal sleeve 35. At its outer end the spring 33 bears against a pad 36 on the outer or free end of the movable sleeve 32. .The movable sleeve 32 is held against escape from the fixed sleeve 3| by a :bolt 31 secured to sleeve 3| andprojecting through a longitudinal slot 38 in sleeve 32. This permits the movable sleeve 32 to work inwardly against the spring 33 within the limits of the slot 38, but said bolt 31, normally in the inner end of slot 38, prevents the movable sleeve 32 from escaping under the action of spring 33.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, til n tic c v t on f om such deta may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:

l. In a wheeled crane having an upstanding elevator frame, an elevator carriage vertically movably mounted on the frame and from the pe end o wh ch t cr n oom ,prqie t e a dl li t otksiru i a a dmean m untin the lift fork structure on the elevator carriage o folding f cma r a a d n oi ctingpos t q below t e bea J an up ta din ou of the w y position; a releasable latch fixed with respect to the carriage in position to hold the lift fork structure in said out-of-the-way position; said releasable latch comprising a fixed yoke including spaced portions, a latch pin carried by the yoke and extending in slidable relationthrough'said portions,:a-collar on the pin within the yoke,. a compression spring about the pin between the collar and one of said portions urging the pin in one direction, and manually operated means connected to the pin to urge it in the opposite direction.

2. In a wheeled crane having an upstanding elevatorframe, an elevator carriage vertically 15' movably mounted on the frame and from the upper end of which the crane boom projects rearwardly, a lift fork, structure, and means mounting-the lift fork structure on the elevator carriage for folding from a rearwardly projecting position below the boom to an upstanding out of the way position; a releasable latch fixed with respect to ,the carriage in position to hold the lift fork structure in said out-ofthe-.-way position; said releasable latch comprising a fixed yoke including spacedportions, a latch pin carriedby theyoke and extending in aslidable relation through said portions, a collar on the pin within the yoke, a compression spring about the pin betweenthe collar and one of said portions urging the pin in one direction, an eccentric cam transversely pivoted on the pin exteriorly of the yoke and working against the outside of said one portion of the yoke, and

-a lever on the cam to rotate'thesame.

3. In a wheeled crane including an upstanding elevator frame having an elevator carriage vertically movably mounted thereon, and said carriage being fitted with a rearprojecting boom having a depending portion adjacent the carriage; a lift fork structure, a pivotal mount securing the lift fork structure on the elevator carriage for folding from a rearwardly projecting working position to an upwardly projecting out-of-the-way position, alongside said depending portion of the boom, and means to.releasably latch the structure in said last named position.

4. In a wheeled crane includingan upstanding elevator frame havingan elevator carriage vertically movablymounted thereon, and 'said .carriage being fitted with a rear projecting boom; a lift fork structure, a pivotal mount securing the lift fork structure in connection with the elevator carriage for folding from a rearwardly projecting working position to an upwardly .projecting out-of-the-way position, and means to releasably latch thestructure in saidlast named position; the .boom including a dependent front end portion, and said' structure including a fork leg which, when the structure is folded, is disposed alongside said portion, astop onsaid porhim ga n w i h t e leg hen a uts, and sai latch means being mountedonsaid portionand engaging the leg.

said structure on the carriage at .its ,lower end f f l ing of th l ss from a rea wardly proiect ng Watkins position to an u standin posiion a ongside said depending p rtion; .a stop on said p r ion to engage one le and limit .119- ward folding movement thereof and-a vertical y movalele upwar ily releegme latc h pin mounted UNITED STATES PATENTS 22h??? $3 152; 3?; 33);? $$efis 1 22 5 333 5 m 353 111% G. LE TOURNEAU. 5 ;;ggg;ggg 3:5 g1; 13;; REFERENCES CITED $332,??? i iifr na aiiiiiflfii j $323 The following references are of record in the 2,419,813 Berchtold Apr. 29, 1947 file of this patent: 

